Hi everyone,

Is there a way to match perfectly two motion blur from two different render engine ?

For exemple, I have a mesh that will be rendered in Maya using Vray, but I need this mesh in Houdini because it will emit smoke and will hide some smoke, so I need my motion blur to match with the Vray one.

Is there some parameters that matches exactly between these two ?

(and I don't want to use Houdini Engine)

Thanks !

Tom

i'm not sure if it is possible to get a 100% match.
tried it with mantra and prman and it never worked 100%

the route we went were either:
–> creating a deep shadow map from other renderer
–> accessing this dsm inside the mantra-shader and use this as hold-out

or you write out deep data (exr2) from mantra and vray and deep comp them
that should remove the need of matching mblur for holdout reasons

Seems complicated
Thanks

I have combined renders from vray and mantra before. Worked for what I needed, but dont expect it to be 100% as infernalSpawn said.
Just make sure you are using object sub sampling for motion blur in both packages as I dont think you can use velocity blur in vray (actually you may be, cant remember, havent used vray for a while).
Set your objects in houdini to use “Geometry Velocity Blur” (Render tab/Sampling tab) and you may need to timeblend node on your mesh to allow for sub frame interpolation of the mesh.
Make sure your houdini camera shutter time matches in vray
For the mantra node make sure shutter offset matches vray and that Geo time samples match vray too.
I think that should do it, or at least get you as close as you will get. Maybe mess with the samples to get the noise in the blur to match with vray perceptually.

Well I'm currently testing with deep, and it works sooooo well !
But I didn't try with vray also, I don't know how much time it will take.

Thanks for advice JordanWalsh !